Correct Answer: 5
Explanation:
Arithmatic mean = sum/members
=> (1x1 + 2x2 + 3x3 + 4x4 + 5x5 + 6x6 + 7x7) / (1 + 2 + 3 + 4 + 5 + 6 + 7)
=> 140/28 = 5